The present invention generally relates to a process and to a system for coating a feed composition with feed additives. More particularly, the present invention is directed to a system in which a liquid suspension containing a feed additive is applied to feed pellets and to a system for diluting and applying liquid additives to feed pellets. The additives can be, for instance, feed supplements, vitamins, enzymes, antioxidants, flavorants, and the like.
Animal feedstuffs used to feed, for instance, poultry, cattle, and swine, are generally made from grains, including wheat, barley, and corn. In producing the feed, the raw ingredients are typically mixed together and milled to a particular size. The granulated stock is then subjected to various process steps in producing a pelletized feed. In particular, during production of the feed pellets, the raw ingredients are cooked and exposed to high temperatures.
In some applications, once the feed pellets or feed granules are formed, it is desirable to add other various additives to the feed. For instance, these additives may include diet supplements, such as vitamins and flavorants, additives that aid in the digestion of the feed, such as enzymes or additives that are beneficial to the environment by reducing elements that are accumulating in the soil. Unfortunately, many feed additives cannot be added during production of the feed because of their sensitivity to higher temperatures and other process conditions. Thus, many additives must be combined with the feed after the feed pellets or feed granules are formed.
Common additives that are applied to animal feeds can be either liquids or solids. When the additive is in solid form, the additive is typically combined with a liquid and the resulting suspension is applied to the feed material. Various problems exist, however, in preventing the additive from settling in the suspension, in handling the suspension, and in applying the suspension uniformly to the feed material. Also, problems have been encountered in selecting a proper liquid carrier for the solid additive.
When the additive is in liquid form, the additive can be applied directly to the feed composition. In some systems, however, the liquid additive is diluted and possibly combined with other liquid additives before being applied to the animal feed.
The present invention is generally directed to improved additive handling systems for applying solid and liquid additives to a feed composition. The systems of the present invention are adapted to apply additives continuously and uniformly to the feed. Other advantages and benefits will be described or will be made apparent from the following description.
The present invention is directed to various improvements in processes and systems for applying additives to a feed composition.
Accordingly, it is an object to the present invention to provide an improved system and process for applying a liquid suspension to a feed composition.
It is another object to the present invention to provide a processing system for forming a liquid suspension and for preventing solid particles in the suspension from settling prior to application.
Another object to the present invention is to provide a processing system for uniformly applying a liquid suspension to a feed composition.
It is another object to the present invention to provide an improved processing system for applying liquid additives to a feed composition.
Another object to the present invention is to provide a processing system for diluting liquid additives, mixing together different liquid additives, and uniformly applying the mixture to a feed composition.
Still another object to the present invention is to provide continuous systems for applying additives to an animal feed composition.
These and other objects to the present invention are achieved by providing a system for applying a suspension containing a solid feed additive to a feed composition. The system includes a solid additive reservoir and a liquid carrier reservoir for containing and supplying a solid feed additive and a liquid carrier respectively to the system. The solid additive reservoir and the liquid carrier reservoir are in communication with at least a first mixing subsystem and a second mixing subsystem. Each of the mixing subsystems are designed to receive preselected amounts of the solid additive and the liquid carrier and to mix the solid additive and liquid carrier into a suspension for application to a feed composition.
More particularly, the system includes at least two separate mixing subsystems so that a first liquid carrier and solid additive suspension can be dispensed while a second liquid carrier and solid additive suspension is mixing. In this manner, a continuous flow of the suspension can be fed to a dispensing device.
Each of the mixing subsystems can include a mixing conduit or pipe configured to circulate the suspension to and from a holding tank. In order to circulate the suspension, the mixing pipe can be in communication with a pump. In order to mix the liquid carrier and the solid additive, the mixing pipe also contains a mixing device. For instance, in one embodiment, the mixing pipe can be connected to a eductor where the solid additive and liquid carrier are combined.
In order to measure the amounts of the liquid carrier and solid additive fed to each mixing subsystem, the system can include load cells at different locations. For instance, in one embodiment, a load cell can be placed at the solid additive reservoir for measuring the amount of solid additive leaving the reservoir. In order to measure the amount of liquid carrier, the liquid carrier can be fed to each holding tank, which can be equipped with a load cell.
Once a suspension is formed, the mixing subsystems deliver the suspension to a dispensing device. The dispensing device includes a plurality of nozzles that convert the suspension into a spray which is directed onto a feed composition. In one embodiment, the nozzles can combine air with the suspension in order to form a spray. In order to prevent clogging, the nozzles each can include a nozzle cleaning device. For instance, each nozzle can be equipped with a retractable needle which is forced through the nozzle a periodic intervals.
The solid additive and liquid carrier suspension can be applied to the feed composition in a design spray chamber or rotating drum. The drum rotates in order to promote mixing between the suspension and the feed composition. Of particular advantage, the rotating drum spray device lowers liquid holdup in the vessel, lowers fines due to the pellets falling apart, and promotes uniform coverage of the additive on the pellets. The drum can be positioned at an angle so that the feed composition flows through the drum due to the force of gravity. The drum can also include a load cell for monitoring the flow rate of the feed composition through the drum.
These and other objects of the present invention are also achieved by providing a system for diluting, combining and applying liquid feed additives to a feed composition. The system is configured to feed a dilution agent and one or more liquid additives to at least two mixing subsystems. As described above, two or more mixing subsystems are configured to combine the liquid ingredients and to apply them continuously to a feed composition.
In this system, preferably each mixing subsystem includes a mixing tank where a dilution agent and at least one liquid additive are combined and mixed. Each mixing tank can contain a load cell for measuring the amounts of the ingredients fed to the tank.
Once the dilution agent and at least one liquid additive are combined, the resulting solution is converted into a spray and applied to a feed composition.
Other objects, features, and aspects of the present invention are discussed in greater detail below.